Implement meeting assistant v1

MeetingAssistant/Summary/IMeetingSummaryPipeline.cs

@@ -0,0 +1,14 @@
+using MeetingAssistant.MeetingNotes;
+
+namespace MeetingAssistant.Summary;
+
+public interface IMeetingSummaryPipeline
+{
+    Task<MeetingSummaryRunResult> RunAsync(MeetingSessionArtifacts artifacts, CancellationToken cancellationToken);
+}
+
+public sealed record MeetingSummaryRunResult(
+    string SummaryPath,
+    string AgentResponse,
+    bool Succeeded = true,
+    string? Error = null);